A sulfur oxide storage material contains a magnesium-aluminum spinel
(MgO.Al.sub.2 O.sub.3) and can be used as a so-called "sulfur trap" to
remove sulfur oxides from oxygen-containing exhaust gases of industrial
processes. In particular, it can be used for the catalytic purification of
exhaust gas from internal-combustion engines to remove the sulfur oxides
from the exhaust gas in order to protect the exhaust gas catalysts from
sulfur poisoning. The material displays a molar ratio of magnesium oxide
to aluminum oxide in the range of over 1.1:1, and the magnesium oxide
present in stoichiometric excess is homogeneously distributed in a highly
disperse form in the storage material.